"It's hard to even conceive of how we would do what we do without the amazing number of processes and techniques he pioneered. All visual effects professionals and movie fans owe him a debt of gratitude."

Look Effects has built on Mr Vlahos' achievements to create work for the movies Avatar, The Life of Pi and the upcoming Superman film, Man of Steel.

Mr Vlahos's techniques were used in dozens of Disney movies

Six-month idea

Mr Vlahos was not the first to use a blue-screens - earlier versions of the technique can be seen in films including The Thief of Bagdad, and The Ten Commandments.

But he is credited with developing a way to use it that minimised some objects appearing to have a strange looking glow as a side-effect.

He called his invention the colour-difference travelling matte scheme.

Like pre-existing blue-screen techniques it involves filming a scene against an aquamarine blue-coloured background.

This is used to generate a matte - which is transparent wherever the blue-colour features on the original film, and opaque elsewhere. This can then be used to superimpose a separately filmed scene or visual effects to create a composite.

Mr Vlahos's breakthrough was to create a complicated laboratory process which involved separating the blue, green and red parts of each frame before combining them back together in a certain order.

He also noted in a patent filing that the process allowed the blue-screen procedure to cope with glassware, cigarette smoke, blowing hair and motion blur which had all caused problems for earlier efforts.

Movie studio MGM had commissioned him to invent it. Mr Vlahos later noted that it had taken him six months of thought to come up with the idea, much of it spent staring out onto Hollywood Boulevard.

The diagram used to outline Mr Vlahos's original blue-screen colour separation processing technique

He later created a "black box" - which he called Ultimatte - to handle the process, first for film and then electronically for video.

"It's the absolute building block of all the visual effects that you see in television and movies," added Mr Shenfield.

"It's significance is extraordinary. Everything people like us and others are still built on that fundamental ability to take lots of elements from lots of places and seamlessly mesh them into a new convincing reality.

"Mr Petro - and his family - were pioneers in our industry for which he should be remembered."